Transmission mechanims for automobiles.



R; E. CARSWELL. TRANSMISSION MECHANISM FOR AUTOMOBILES.

APPLICATION FILED APR. I3. I914.

Patented June 15, 1915.

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THE NORRIS PETERS 60., PHOTO-LITHO.. w'ASH/Nulum. a u.

ROBERT E. CARSWELL, OF MINNEAPOLIS, MINNESOTA.

TRANSMISSION MECHANISM FOR AUTOMOBILES.

To all whom it may concern Be it known that I, ROBERT E. CARSWELL, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certaln new and useful Improvements in Transmlssion Mechanism for Automobiles; and I do hereby declare the following to be a full, clear, and'exact description of the inventlon, such aswill enable others skilled in the art to which it appertains to make and use the same. 7 v

My invention has for its object to provide an improved transmission mechanism for automobiles or motorj propelled vehicles, wherein a frictional differential gear mechanism having non-adjustable or definitely lo cated friction wheels, is used'in combination with a reversible variable speed toothed gear mechanism; and wherein the motion transmitted from the engine is either reversed or converted into the desired speed before it is transmitted to the frictional differential gear mechanism. v

0 such ends, generally stated, the invention consists of the novel devices and combinations. of devices hereinafter described and defined in theclaims.

In the accompanying drawings which illustrate the invention, like characters indi cate like parts throughout the several views;

eferring to the drawings: Figure 1 is a plan view showing the improved transmis sion mechanism applied to an automobile; Fig. 2 is a view partly in horizontal section and partlyin plan showing the reversible variable speed gear mechanism; and Fig. 3 is a section taken approximately on the line m w on Fig. 1, some parts beinglshown in full. 1

Of the parts of the chassis of the automobile, it is only desirable'to note the frame work 1, front wheels 2, rear axle 3, rear or traction wheels 4 and the engine 5; The rear traction wheels 4 are mounted on the rear axle 3 for differential rotary movements, and on their hubs, they carry sprockets 6. he engine crankshaft proper, at its rearwardly projecting end, is, as showmconnected by a knuckle joint? to an axially alined shaft 8 journaled in a gear casing 9 rigidly secured on the framework 1. The casing 9, incloses the coeperating spur gears of the reversible variable speed transmission device. The front end of a shaft 10, that is Specification of Letters Patent.

Patented June 15, 1915..

Application filed April 13, 1914. Serial No. 831,358.

axially alined with the shaft 8, is also journaled in the casing 9, and its rear end is, as shown, connected by a knuckle joint 11 to the front end of an axially alined shaft 12 that is journaled in a suitable bearing 13 on the framework 1 and is equipped at its rear end with a face friction wheel 14. The face friction wheel 14 runs in frictional engage ment with the peripheries of a pair of peripheral friction wheels 15 that are secured on the inner ends of short axially alined counter shafts 16, which counter shafts are extended transversely of the frame 1 and are journaled in suitable bearings 17 secured on the'sides of the said frame. The outer end of one of the shafts 16 carries a sprocket 18, while the outer end of the other shaft 16 carries a spur gear 19 that meshes with a similar spur gear 20 secured on the inner end of a supplemental counter shaft 21, shown as journaled in a bearing 22 secured on the adjacent side of the frame 1. The outer end of the supplemental counter shaft 21 is provided with a sprocket 18 Sprocket chains 23 run over the sprocket 6 ,on the hubs of the traction wheels 4, and over the alined sprockets 18 and 18 The friction wheels 14 and 15 constitute the frictional differential gear, and it will, of course, be understood that the gears 19 and 20 and supplemental shaft 21 are provided for the purposeof transmitting motion so that both traction wheels will be driven in the same direction from the reversely rotated friction wheels 15, which friction wheels are located'on opposite sides of the axis of the face friction wheel 14 which drives them. The said friction wheels 15 are always kept at their maximum distance from the axis of the face friction wheel 14 where they have the greatest driving efliciency. It is a well known fact that when peripheral friction wheels are moved close to the axis of the coeperating face friction wheel, there is a very greatly increased loss in power due to slippage or conflicting friction. 7

It is important to note that in this improved transmission mechanism, the cooperating friction wheels 14 and 15 afford a frictional difierential gear mechanism. However, the said friction wheels are preferably, also, used as a friction clutch and this may be very easily accomplished simply by givingthe face friction wheel 14 a very within cavity of the bearing .13.

slight movement, approximately onesixteenth of an iiich toward and from the cooperating peripheral friction wheels 15. The knuckle joint 11 will permit the re quired slight endwise movement of the shaft section 12 to which the friction wheel 14 is secured, necessary to accomplish the above result. As shown in Fig. 3, a pair of thrust collars 39 and and an interposed coiled spring 41 are placed on the shaft sectior imli2 e thrust collar 39 bears against a shoulder on the said. shaft section, and the collar 40 is engaged by a depending arm 42 of a rock shaft 43 that is journaled' in suitable bear ing's on the frame 1 and provided with an upwardly extendedarm 44 that is connected to a lever operated link 45. The link willpreferably be connected to a foot lever, not shown, so that the friction wheel 14will be held in frictional driving engagement with the wheels 15, when and only when the lever. 44 is drawn forward by the pressure on the said foot lever. This foot lever construction is well understood, and hence, not illustrated. It will thus be seen that the friction wheels 14, 15-15 alforda combined friction clutch and frictional differential gear mechanism.

- Any suitable, or any of the many well known variable speed reversing gear idevices may beemployed to connect the adj acent ends of the engine driven shafts 8 and 10,'and these gears are preferably located 185} within the casing 9, As shown, they comprise as follows? Thenumerals 24 and 25 indicate spur gears that are arranged to slide upon the shaft 8, but are caused to retate therewith by a long key 26. The gear tl1ereof, he gears 25 is larger than the gear 24 and both of the gears are provided with grooved hubs that are engaged by shipper arms 27. One of the shipper arms 27 is secured to an endwise movable adjusting rod 28, and the other is secured to an adjusting sleeve 29, which latter surrounds the said rod 28. The said rod and sleeve are mounted in suitable bearings on the casing, and by adjustments 24 and 25 maybe independently a lid on the shaft 8. The gear 24 has a half clutch30 that is engageable with the half clutch '31 of a spur pinion 32 secured on the adjacent end of the shaft 10. The pinion 32'meshes with-a spur gear 33 carried by a counter shaft 34 journaled in suitable bearings in the casing 9. This counter shaft 34 also carries spur gear's'35,

' 36 and '37. The gear 37 runs in mesh with an intermediate gear 38 which is suitably journaled to the casing 9 and is shown in part in Fig. 2. When the gear 24 is'shifted so as to engage the half clutch 30 with the half clutch 31 of the pinion 32, the shaft'or shaft section 10 will berotated at the same speed as the shaft or shaft, section}, or, in

shifted into engagement with the gear 35, a

the shaftlO willbe-rotated at a higher rate of speed than the shaft 8, but inthe same direction. When the gear 25 is shifted into mesh with the gear 36, the shaft 10 willvbe driven at another speed but in the same direction'as the, shaft 8; and when the said gear 25 is shifted into mesh with the intermediate gear 88, the saidjshaft 10 will be driveniri, a direction reverse from that of thesaid shaft 8; V V V r ,With the arrangementabove described, it is evident that the speed and power-of the engine are transmitted variably and in either direction to the driving friction wheel 14 of the frictional difier'ential' gear, and

that it is then differentially transmitted to V the traction wheels through the said friction gear. This is a highly'desirableand ther oughly practicable arrangement for automo bile transmission mechanism. i

The three friction wheels14,;1515 are stated as permanently located to distinguish them from frictional 'wheels' that arerelatively adjustable, for the purpose of varying speed; The very slight movement given to the wheel 14, necessary to attain the frictional clutch action, is not such an adjust ment as to render the above statement ma terially incorrect. Y What I claim is: g

1. The combination with a motor and traction wheels, of a motor propelled vehicle, a variable speed toothed gear drive driven from said motor, andca frictional gear mechanism having three coiiperating friction wheels, one of which is driven from said toothed gear drive, and the other two of which are connected, one to each of the traction wheels. I 1 q 2-. The combination with a motor and traction wheels, of a motor propelled vehicle, a variable speed toothed gear drive driven from said motor, a frictional gear mechanism having three coiiperating friction wheels, one of which is driven from said toothed gear drive and the other two of which are connected, one to each of the traction wheels, and means for moving the first noted of said friction wheels into and outof engagement with the other two frietion wheels, whereby they are caused to operate as acombined frictional transmission and clutch.

3rThe combination with threecotperat' 'ing permanently located friction wheels,

two thereof being driven from the j third friction wheel and each ofsaidty'vo driven wheels being connected toacorresponding traction wheel, a reversible variable speed toothed gear drive, shaft connecting-said motor tonne of the elements of said toothed gea1':driv'e,.and a countershaft connecting" hicle,

another of the elements of said toothed gear drive to the third or driving member of said friction wheels.

4. The combination with the motor, the traction wheels and the variable speed toothed gear drive of a motor propelled veof three cooperating friction wheels, the first being driven from said toothed gear drive, and the other two being connected tov the respective traction wheels, the said three friction wheels being permanently located, but the said first friction wheel having a slight movement to throw the same into and out of frictional driving action on the said cooperating friction wheels, whereby the 1 Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, I). C. 

